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View Full Version : Seedless watermelons...I don't get it.


ivylass
07-06-2003, 07:52 AM
It was the 4th, so we had to have a watermelon. Ivylad picked up a seedless one.

But it wasn't seedless. It had the white seeds, but not the black ones.

Which begs the questions...

What's the difference between white and black watermelon seeds?

And, how do you grow seedless watermelon? If the fruit is sterile(no seeds) how do you get the next crop?

Mangetout
07-06-2003, 09:12 AM
The small flattish white seeds in a watermelon are undeveloped because they are not fertilised; the seedless melon cultivar is grown from seeds, but these seeds are the result of a specific cross-pollination between two different varieties (or perhaps species) that happens to result in infertile offspring.

Members of Cucurbitaceae will often form fruits even if pollination fails (if the cucumbers you buy in the supermarket had been pollinated, they would be curved and very bitter).

Many other seedless fruits (such as grapes) are either propagated from cuttings originating from a mutant, non-seeding strain (which would quickly have otherwise died out), or are the result of ordinary plants being treated with the right hormones to promote fruit development in the absence of pollination.

Mangetout
07-06-2003, 09:16 AM
I just re-read that and I don't think I was clear enough; with the watermelons, you have two different varieties, A and B - when you cross A with B you get seeds - the offspring (C) is always infertile (due to some sort of genetic constraints) - when you want more seeds to grow seedless watermelons, you start by crossing A with B again.

(somebody else will be along shortly to point out your misuse of 'begs the question)

Reeder
07-06-2003, 10:49 AM
http://ask.yahoo.com/ask/20010611.html

Joe Random
07-06-2003, 11:39 AM
Originally posted by Mangetout
(somebody else will be along shortly to point out your misuse of 'begs the question) Ask, and ye shall receive.From the Common Errors in English (http://www.wsu.edu/~brians/errors/begs.html) website:

An argument that improperly assumes as true the very point the speaker is trying to argue for is said in formal logic to "beg the question." Here is an example of a question-begging argument: "This painting is trash because it is obviously worthless." The speaker is simply asserting the worthlessness of the work, not presenting any evidence to demonstrate that this is in fact the case. Since we never use "begs" with this odd meaning ("to improperly take for granted") in any other phrase, many people mistakenly suppose the phrase implies something quite different: that the argument demands that a question about it be asked--raises the question. If you're not comfortable with formal terms of logic, it's best to stay away from this phrase, or risk embarrassing yourself.

Smeghead
07-06-2003, 10:57 PM
Most of the time, seedless fruits are aneuploid - that is, they have an odd number of each chromosome. Humans are diploid, meaning we have two of each chromosome. Modern commercial strawberrys are octoploid, and so on. When the number is even, chromosomes can pair up nicely during meiosis and everything goes well. When the number is odd, you end up with extras of some chromosomes and shorted on others, so gametes die quickly instead of forming fully. White watermelon "seeds" are, in fact, abortuses. I can't remember what ploidy seedless watermelons are offhand. I want to say they're pentaploid, but I'm not sure. I know bananas are triploid, though, which is why you just get those little black specks instead of marble-sized seeds.

Desmostylus
07-06-2003, 11:10 PM
According to Reeder's link above, Smeghead, they're triploid.

pkbites
07-06-2003, 11:36 PM
I asked this question looooooooooooong ago.


After years of buying "seedless" watermelons I've found that those that are very ripe have no seeds. Zero. Not even the white ones. Now why is that? Explain why ripeness=no seeds at all.

Let me tell you, a ripe melon with absolutely no seeds is pure extacy.
This 4th of July weekened I juiced half of a ripe seedless and froze the juice into popcicles. Indescribable flavor!

bibliophage
07-07-2003, 01:34 AM
Cecil Adams on How do they grow more seedless fruit? (http://www.straightdope.com/classics/a5_044.html)

bibliophage
07-07-2003, 01:37 AM
And Cecil Adams again (http://www.straightdope.com/columns/020524.html) On the subject of begging the question, it occurred to me to say "invite" or "demand" lest I hear from persons such as yourself. But "beg" had the element of puppy-dog enthusiasm I was after. I was using these words in a manner congruent with their plain meaning, and while they also happen to be the term for a certain logical fallacy, I figured that no one would misunderstand my intent. And no one has. I recognize, however, that people need an outlet for their hostility, and better this than mailbox bombs. So, has your stress been reduced? Good. Now piss off.

Adelita
07-07-2003, 01:38 AM
I have *never* thought of watermelons as fertile or infertile, till now. :eek: Thanks for the, uh, information! :p